Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 3.749
Filter
1.
Med Sci Monit ; 30: e945091, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38736218

ABSTRACT

Alzheimer's disease is the most common form of dementia and includes cognitive, personality, and behavioral changes. The 2024 report from the Alzheimer's Association estimated that 6.9 million adults >65 years in the US are currently living with Alzheimer's disease. Modeling studies predict that this number will double by 2050, and associated healthcare costs will reach $1 trillion. In June 2021, regulatory approval of aducanumab, a humanized recombinant monoclonal antibody to amyloid ß, initially raised expectations for improved disease-modifying therapy. However, in February 2024, production of aducanumab and a post-marketing clinical trial ceased in the US due to the costs and limitations of aducanumab therapy. In March 2024, biobank data identified significant modifiable risk factors for Alzheimer's disease, including diabetes mellitus, exposure to nitrogen dioxide (a proxy for air pollution), and the frequency of alcohol intake. Therefore, modification of identifiable risk factors, combined with testing for disease-susceptibility genes, could be the most effective approach to reduce the incidence. This article aims to review the current status of disease-modifying therapies and prevention of Alzheimer's disease.


Subject(s)
Alzheimer Disease , Alzheimer Disease/prevention & control , Alzheimer Disease/drug therapy , Humans , Risk Factors , Antibodies, Monoclonal, Humanized/therapeutic use , Amyloid beta-Peptides/metabolism
2.
J Prev Alzheimers Dis ; 11(3): 589-600, 2024.
Article in English | MEDLINE | ID: mdl-38706275

ABSTRACT

BACKGROUND: Alzheimer's disease (AD), the most common type of irreversible dementia, is predicted to affect 152 million people by 2050. Evidence from large-scale preventive randomized controlled trials (RCTs) on modifiable risk variables in Europe has shown that multi-domain lifestyle treatments for older persons at high risk of dementia may be practical and effective. Given the substantial differences between the Chinese and European populations in terms of demographics and living conditions, direct adoption of the European program in China remains unfeasible. Although a RCT has been conducted in China previously, its participants were mainly from rural areas in northern China and, thus, are not representative of the entire nation.There is an urgent need to establish cohorts that represent different economic, cultural, and geographical situations in order to explore implementation strategies and evaluate the effects of early multi-domain interventions more comprehensively and accurately. MEDTODS: We developed an integrated intervention procedure implemented in urban neighborhood settings, namely China Initiative for Multi-Domain Intervention (CHINA-IN-MUDI). CHINA-IN-MUDI is a 2-year multicenter open-label cluster-randomised controlled trial centered around a Chinese-style multi-domain intervention to prevent cognitive decline. Participants aged 60-80 years were recruited from a nationally representative study, i.e. China Healthy Aging and Dementia Study cohort. An external harmonization process was carried out to preserve the original FINGER design. Subsequently, we standardized a series of Chinese-style intervention programs to align with cultural and socioeconomic status. Additionally, we expanded the secondary outcome list to include genomic and proteomic analyses. To enhance adherence and facilitate implementation, we leveraged an e-health application. RESULTS: Screening commenced in July 2022. Currently, 1,965 participants have been randomized into lifestyle intervention (n = 772) and control groups (n = 1,193). Both the intervention and control groups exhibited similar baseline characteristics. Several lifestyle and vascular risk factors were present, indicating a potential window of opportunity for intervention. The intervention will be completed by 2025. CONCLUSIONS: This project will contribute to the evaluation of the effectiveness and safety of intervention strategies in controlling AD risk and reducing clinical events, providing a basis for public health decision-making in China.


Subject(s)
Cognitive Dysfunction , Aged , Female , Humans , Male , Middle Aged , Alzheimer Disease/prevention & control , China/epidemiology , Cognitive Dysfunction/prevention & control , Life Style
3.
Zhongguo Zhong Yao Za Zhi ; 49(4): 902-911, 2024 Feb.
Article in Chinese | MEDLINE | ID: mdl-38621897

ABSTRACT

Alzheimer's disease(AD), vascular dementia(VD), and traumatic brain injury(TBI) are more common cognitive impairment diseases characterized by high disability and mortality rates, imposing a heavy burden on individuals and their families. Although AD, VD, and TBI have different specific mechanisms, their pathogenesis is closely related to the nucleotide-binding oligome-rization domain-like receptor protein 3(NLRP3). The NLRP3 inflammasome is involved in neuroinflammatory responses, mediating microglial polarization, regulating the reduction of amyloid ß-protein(Aß) deposition, neurofibrillary tangles(NFTs) formation, autophagy regulation, and maintaining brain homeostasis, and synaptic stability, thereby contributing to the development of AD, VD, and TBI. Previous studies have shown that traditional Chinese medicine(TCM) can alleviate neuroinflammation, promote microglial polarization towards the M2 phenotype, reduce Aß deposition and NFTs formation, regulate autophagy, and maintain brain homeostasis by intervening in NLRP3 inflammasome, hence exerting a role in preventing and treating cognitive impairment-related diseases, reducing psychological and economic pressure on patients, and improving their quality of life. Therefore, this article elucidated the role of NLRP3 inflammasome in AD, VS, and TBI, and provided a detailed summary of the latest research results on TCM intervention in NLRP3 inflammasome for the prevention and treatment of these diseases, aiming to inherit the essence of TCM and provide references and foundations for clinical prevention and treatment of cognitive impairment-related diseases with TCM. Meanwhile, this also offers insights and directions for further research in TCM for the prevention and treatment of cognitive impairment-related diseases.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Amyloid beta-Peptides/metabolism , Medicine, Chinese Traditional , Quality of Life , Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/prevention & control
4.
Biosci Rep ; 44(4)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38577975

ABSTRACT

Since 1975, the incidence of obesity has increased to epidemic proportions, and the number of patients with obesity has quadrupled. Obesity is a major risk factor for developing other serious diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular diseases. Recent epidemiologic studies have defined obesity as a risk factor for the development of neurodegenerative diseases, such as Alzheimer's disease (AD) and other types of dementia. Despite all these serious comorbidities associated with obesity, there is still a lack of effective antiobesity treatment. Promising candidates for the treatment of obesity are anorexigenic neuropeptides, which are peptides produced by neurons in brain areas implicated in food intake regulation, such as the hypothalamus or the brainstem. These peptides efficiently reduce food intake and body weight. Moreover, because of the proven interconnection between obesity and the risk of developing AD, the potential neuroprotective effects of these two agents in animal models of neurodegeneration have been examined. The objective of this review was to explore anorexigenic neuropeptides produced and acting within the brain, emphasizing their potential not only for the treatment of obesity but also for the treatment of neurodegenerative disorders.


Subject(s)
Anti-Obesity Agents , Neuropeptides , Neuroprotective Agents , Obesity , Humans , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Animals , Obesity/drug therapy , Obesity/metabolism , Neuropeptides/metabolism , Neuropeptides/pharmacology , Neuropeptides/therapeutic use , Anti-Obesity Agents/pharmacology , Anti-Obesity Agents/therapeutic use , Neurodegenerative Diseases/drug therapy , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/prevention & control , Hypothalamus/drug effects , Hypothalamus/metabolism , Hypothalamus/pathology , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/prevention & control , Brain/drug effects , Brain/metabolism , Brain/pathology , Eating/drug effects
5.
Neurobiol Aging ; 139: 20-29, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38583392

ABSTRACT

Brazilian green propolis (propolis) is a chemically complex resinous substance that is a potentially viable therapeutic agent for Alzheimer's disease. Herein, propolis induced a transient increase in intracellular Ca2+ concentration ([Ca2+]i) in Neuro-2A cells; moreover, propolis-induced [Ca2+]i elevations were suppressed prior to 24-h pretreatment with amyloid-ß. To reveal the effect of [Ca2+]i elevation on impaired cognition, we performed memory-related behavioral tasks in APP-KI mice relative to WT mice at 4 and 12 months of age. Propolis, at 300-1000 mg/kg/d for 8 wk, significantly ameliorated cognitive deficits in APP-KI mice at 4 months, but not at 12 months of age. Consistent with behavioral observations, injured hippocampal long-term potentiation was markedly ameliorated in APP-KI mice at 4 months of age following repeated propolis administration. In addition, repeated administration of propolis significantly activated intracellular calcium signaling pathway in the CA1 region of APP-KI mice. These results suggest a preventive effect of propolis on cognitive decline through the activation of intracellular calcium signaling pathways in CA1 region of AD mice model.


Subject(s)
Alzheimer Disease , Calcium , Cognitive Dysfunction , Disease Models, Animal , Propolis , Animals , Propolis/therapeutic use , Propolis/administration & dosage , Propolis/pharmacology , Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Alzheimer Disease/psychology , Alzheimer Disease/etiology , Cognitive Dysfunction/etiology , Cognitive Dysfunction/prevention & control , Cognitive Dysfunction/drug therapy , Calcium/metabolism , Mice, Transgenic , Calcium Signaling/drug effects , Long-Term Potentiation/drug effects , Male , Amyloid beta-Peptides/metabolism , CA1 Region, Hippocampal/metabolism , CA1 Region, Hippocampal/drug effects , Mice
6.
Food Funct ; 15(8): 4233-4245, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38517352

ABSTRACT

The aggregation of ß-amyloid (Aß) peptides to form amyloid plaques is one of the primary hallmarks for Alzheimer's disease (AD). Dietary flavonoid supplements containing hesperetin have an ability to decline the risk of developing AD, but the molecular mechanism is still unclear. In this work, hesperetin, a flavanone abundant in citrus fruits, has been proven to prevent the formation of Aß aggregates and depolymerized preformed fibrils in a concentration-dependent fashion. Hesperetin inhibited the conformational conversion from the natural structure to a ß-sheet-rich conformation. It was found that hesperetin significantly reduced the cytotoxicity and relieved oxidative stress eventuated by Aß aggregates in a concentration-dependent manner. Additionally, the beneficial effects of hesperetin were confirmed in Caenorhabditis elegans, including the inhibition of the formation and deposition of Aß aggregates and extension of their lifespan. Finally, the results of molecular dynamics simulations showed that hesperetin directly interacted with an Aß42 pentamer mainly through strong non-polar and electrostatic interactions, which destroyed the structural stability of the preformed pentamer. To summarize, hesperetin exhibits great potential as a prospective dietary supplement for preventing and improving AD.


Subject(s)
Amyloid beta-Peptides , Caenorhabditis elegans , Hesperidin , Hesperidin/pharmacology , Hesperidin/chemistry , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/toxicity , Amyloid beta-Peptides/chemistry , Animals , Caenorhabditis elegans/drug effects , Humans , Alzheimer Disease/metabolism , Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Amyloid/metabolism , Molecular Dynamics Simulation , Oxidative Stress/drug effects , Protein Aggregates/drug effects
7.
Food Funct ; 15(8): 3920-3938, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38517682

ABSTRACT

Alzheimer's disease (AD) currently lacks effective treatments, making its prevention a critical focus. While accumulating evidence supports that plant-based fermented foods may contribute to AD prevention, the neuroprotective effect of plant-based fermented foods on AD has not been comprehensively reviewed. In this study, we conducted a systematic review of preclinical studies on the efficacy of plant-based fermented foods in AD. The literature search was based on databases including PubMed, Embase, Web of Science, and Scopus. The PICO approach was employed for report inclusion, and each report was assessed for risk of bias using the SYRCLE's RoB tool. From the analysis of 25 retrieved reports, we extracted essential details, including bibliographic information, animal models and characteristics, sources of plant-based fermented foods, dosages, administration routes, durations, and outcome measures. Our findings indicate that plant-based fermented foods may positively impact acute and long-term cognitive function, as well as beta-amyloid-mediated neurodegeneration. This review sheds light on the potential neuroprotective benefits of plant-based fermented foods for various AD-related aspects, including oxidative stress, synaptotoxicity, neuroinflammation, tau hyperphosphorylation, dysfunctional amyloidogenic pathways, and cognitive deficits, as observed in rodent models of AD. However, the small number of studies obtained from our literature search and the finding that many of them were of moderate methodological quality suggest the need for further investigation to substantiate the beneficial potential of this class of functional food for the management of AD.


Subject(s)
Alzheimer Disease , Fermented Foods , Neuroprotective Agents , Alzheimer Disease/prevention & control , Alzheimer Disease/diet therapy , Animals , Humans , Neuroprotective Agents/therapeutic use , Disease Models, Animal , Oxidative Stress/drug effects , Amyloid beta-Peptides/metabolism
8.
Psychogeriatrics ; 24(3): 701-718, 2024 May.
Article in English | MEDLINE | ID: mdl-38528391

ABSTRACT

Curcumin and omega-3 polyunsaturated fatty acids (ω-3 PUFA) are multifunctional compounds which play an important role in Alzheimer's disease (AD) and little has been addressed about the role of these two compounds together in the progression of the disease. There is evidence of the beneficial effect of combined administration of ω-3 PUFA and other dietary supplements such as vitamins and polyphenols in the prevention of AD, although much remains to be understood about their possible complementary or synergistic activity. Therefore, the objective of this work is to review the research focused on studying the effect and mechanisms of action of curcumin, ω-3 PUFA, and the combination of these nutraceutical compounds, particularly on AD, and to integrate the possible ways in which these compounds can potentiate their effect. The most important pathophysiologies that manifest in AD will be addressed, in order to have a better understanding of the mechanisms of action through which these bioactive compounds exert a neuroprotective effect.


Subject(s)
Alzheimer Disease , Curcumin , Dietary Supplements , Fatty Acids, Omega-3 , Neuroprotective Agents , Curcumin/therapeutic use , Curcumin/pharmacology , Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Humans , Fatty Acids, Omega-3/pharmacology , Fatty Acids, Omega-3/therapeutic use , Neuroprotective Agents/therapeutic use , Neuroprotective Agents/pharmacology , Drug Synergism
9.
Methods Mol Biol ; 2785: 15-33, 2024.
Article in English | MEDLINE | ID: mdl-38427185

ABSTRACT

The development of effective prevention and treatment strategies for Alzheimer's disease (AD) and dementia is hindered by limited knowledge of the underlying biological and environmental causes. While certain genetic factors have been associated with AD, and various lifestyle and environmental factors have been linked to dementia risk, the interactions between genes and the environment are not yet fully understood. To identify new avenues for dementia prevention, coordinated global efforts are needed to utilize existing cohorts and resources effectively and efficiently. This chapter provides an overview of current research on risk and protective factors for AD and dementia and discusses the opportunities and challenges associated with population-based approaches.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/genetics , Alzheimer Disease/prevention & control
10.
JAMA Intern Med ; 184(5): 563-572, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38436963

ABSTRACT

Importance: Dementia affects 10% of those 65 years or older and 35% of those 90 years or older, often with profound cognitive, behavioral, and functional consequences. As the baby boomers and subsequent generations age, effective preventive and treatment strategies will assume increasing importance. Observations: Preventive measures are aimed at modifiable risk factors, many of which have been identified. To date, no randomized clinical trial data conclusively confirm that interventions of any kind can prevent dementia. Nevertheless, addressing risk factors may have other health benefits and should be considered. Alzheimer disease can be treated with cholinesterase inhibitors, memantine, and antiamyloid immunomodulators, with the last modestly slowing cognitive and functional decline in people with mild cognitive impairment or mild dementia due to Alzheimer disease. Cholinesterase inhibitors and memantine may benefit persons with other types of dementia, including dementia with Lewy bodies, Parkinson disease dementia, vascular dementia, and dementia due to traumatic brain injury. Behavioral and psychological symptoms of dementia are best treated with nonpharmacologic management, including identifying and mitigating the underlying causes and individually tailored behavioral approaches. Psychotropic medications have minimal evidence of efficacy for treating these symptoms and are associated with increased mortality and clinically meaningful risks of falls and cognitive decline. Several emerging prevention and treatment strategies hold promise to improve dementia care in the future. Conclusions and Relevance: Although current prevention and treatment approaches to dementia have been less than optimally successful, substantial investments in dementia research will undoubtedly provide new answers to reducing the burden of dementia worldwide.


Subject(s)
Dementia , Aged , Humans , Alzheimer Disease/prevention & control , Cholinesterase Inhibitors/therapeutic use , Dementia/prevention & control , Memantine/therapeutic use , Risk Factors , Aged, 80 and over
11.
BJU Int ; 133(4): 358-359, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38504448
12.
Aging Clin Exp Res ; 36(1): 77, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38519775

ABSTRACT

BACKGROUND: Dementia affects 5-8% of the population aged over 65 years (~50 million worldwide). Several factors are associated with increased risk, including diet. The Mediterranean diet (MedDiet) has shown potential protective effects against several chronic diseases. AIMS: This systematic review with meta-analysis aim was to assess the association between adherence to the MedDiet and the risk of dementia in the elderly. METHODS: PRISMA-2020 guidelines were followed. PubMed/MEDLINE and Scopus were searched on 17 July 2023. The Newcastle-Ottawa Scale tool was used to assess the risk of bias. The protocol was pre-registered in PROSPERO (registration number: CRD 42023444368). Heterogeneity was assessed using the I2 test. Publication bias was assessed by visual inspection of the funnel plot and by Egger's regression asymmetry test. The final effect size was reported as OR or HR, depending on the study design of the included studies. RESULTS: Out of 682 records, 21 were included in the analysis. The pooled OR was 0.89 (95% CI = 0.84-0.94) based on 65,955 participants (I2 = 69.94). When only cohort studies were included, HR was 0.84 (95% CI = 0.76-0.94) based on 55,205 participants (I2 = 89.70). When only Alzheimer Disease was considered OR was 0.73 (95% CI = 0.62-0.85) based on 38,292 participants (I2 = 63.85). DISCUSSION: Despite the relatively low risk reduction associated with higher adherence to MedDiet among elderly, it should be considered that this population is the most affected. CONCLUSIONS: Adherence to MedDiet could be an effective non-pharmacological measure to reduce the burden of dementia, even among elderly.


Subject(s)
Alzheimer Disease , Diet, Mediterranean , Aged , Humans , Alzheimer Disease/prevention & control , Cohort Studies , Risk , Research Design
13.
Exp Gerontol ; 190: 112411, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38548241

ABSTRACT

INTRODUCTION: Diverse pathogens (viral, bacterial, fungal) have been associated with Alzheimer's disease (AD) and related traits in various studies. This suggests that compromised immunity, rather than specific microbes, may play a role in AD by increasing an individual's vulnerability to various infections, which could contribute to neurodegeneration. If true, then vaccines that have heterologous effects on immunity, extending beyond protection against the targeted disease, may hold a potential for AD prevention. METHODS: We evaluated the associations of common adult infections (herpes simplex, zoster (shingles), pneumonia, and recurrent mycoses), and vaccinations against shingles and pneumonia, with the risks of AD and other dementias in a pseudorandomized sample of the Health and Retirement Study (HRS). RESULTS: Shingles, pneumonia and mycoses, diagnosed between ages 65 and 75, were all associated with significantly increased risk of AD later in life, by 16 %-42 %. Pneumococcal and shingles vaccines administered between ages 65-75 were both associated with a significantly lower risk of AD, by 15 %-21 %. These effects became less pronounced when AD was combined with other dementias. DISCUSSION: Our findings suggest that both the pneumococcal polysaccharide vaccine and the live attenuated zoster vaccine can offer significant protection against AD. It remains to be determined if non-live shingles vaccine has a similar beneficial effect on AD. This study also found significant associations of various infections with the risk of AD, but not with the risks of other dementias. This indicates that vulnerability to infections may play a more significant role in AD than in other types of dementia, which warrants further investigation.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/immunology , Alzheimer Disease/prevention & control , Aged , Male , Female , Herpes Zoster/prevention & control , Herpes Zoster/immunology , Herpes Zoster Vaccine/immunology , Pneumonia/prevention & control , Pneumonia/immunology , Pneumonia/microbiology , Mycoses/prevention & control , Mycoses/immunology , Aged, 80 and over , Pneumococcal Vaccines/immunology , Risk Factors
14.
J Alzheimers Dis ; 98(2): 387-401, 2024.
Article in English | MEDLINE | ID: mdl-38393906

ABSTRACT

 Alzheimer's disease (AD) affects more than 40 million people worldwide and is the leading cause of dementia. This disease is a challenge for both patients and caregivers and puts a significant strain on the global healthcare system. To address this issue, the Lancet Commission recommends focusing on reducing modifiable lifestyle risk factors such as hypertension, diabetes, and physical inactivity. Passive pulsatile shear stress (PPSS) interventions, which use devices like whole-body periodic acceleration, periodic acceleration along the Z-axis (pGz), and the Jogging Device, have shown significant systemic and cellular effects in preclinical and clinical models which address these modifiable risks factors. Based on this, we propose that PPSS could be a potential non-pharmacological and non-invasive preventive or therapeutic strategy for AD. We perform a comprehensive review of the biological basis based on all publications of PPSS using these devices and demonstrate their effects on the various aspects of AD. We draw from this comprehensive analysis to support our hypothesis. We then delve into the possible application of PPSS as an innovative intervention. We discuss how PPSS holds promise in ameliorating hypertension and diabetes while mitigating physical inactivity, potentially offering a holistic approach to AD prevention and management.


Subject(s)
Alzheimer Disease , Diabetes Mellitus , Hypertension , Humans , Alzheimer Disease/prevention & control , Hypertension/prevention & control , Risk Factors , Delivery of Health Care
15.
J Alzheimers Dis ; 98(2): 361-372, 2024.
Article in English | MEDLINE | ID: mdl-38393913

ABSTRACT

 There is growing awareness that infections may contribute to the development of senile dementia including Alzheimer's disease (AD), and that immunopotentiation is therefore a legitimate target in the management of diseases of the elderly including AD. In Part I of this work, we provided a historical and molecular background to how vaccines, adjuvants, and their component molecules can elicit broad-spectrum protective effects against diverse agents, culminating in the development of the tuberculosis vaccine strain Bacille Calmette-Guérin (BCG) as a treatment for some types of cancer as well as a prophylactic against infections of the elderly such as pneumonia. In Part II, we critically review studies that BCG and other vaccines may offer a measure of protection against dementia development. Five studies to date have determined that intravesicular BCG administration, the standard of care for bladder cancer, is followed by a mean ∼45% reduction in subsequent AD development in these patients. Although this could potentially be ascribed to confounding factors, the finding that other routine vaccines such as against shingles (herpes zoster virus) and influenza (influenza A virus), among others, also offer a degree of protection against AD (mean 29% over multiple studies) underlines the plausibility that the protective effects are real. We highlight clinical trials that are planned or underway and discuss whether BCG could be replaced by key components of the mycobacterial cell wall such as muramyl dipeptide. We conclude that BCG and similar agents merit far wider consideration as prophylactic agents against dementia.


Subject(s)
Alzheimer Disease , Tuberculosis Vaccines , Humans , Aged , BCG Vaccine/therapeutic use , Adjuvants, Immunologic/therapeutic use , Alzheimer Disease/prevention & control , Alzheimer Disease/drug therapy
16.
Eur J Neurol ; 31(5): e16238, 2024 May.
Article in English | MEDLINE | ID: mdl-38323508

ABSTRACT

BACKGROUND AND PURPOSE: The complex aetiology of Alzheimer's disease suggests prevention potential. Risk scores have potential as risk stratification tools and surrogate outcomes in multimodal interventions targeting specific at-risk populations. The Australian National University Alzheimer's Disease Risk Index (ANU-ADRI) was tested in relation to cognition and its suitability as a surrogate outcome in a multidomain lifestyle randomized controlled trial, in older adults at risk of dementia. METHODS: In this post hoc analysis of the Finnish Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), ANU-ADRI was calculated at baseline, 12, and 24 months (n = 1174). The association between ANU-ADRI and cognition (at baseline and over time), the intervention effect on changes in ANU-ADRI, and the potential impact of baseline ANU-ADRI on the intervention effect on changes in cognition were assessed using linear mixed models with maximum likelihood estimation. RESULTS: A higher ANU-ADRI was significantly related to worse cognition, at baseline (e.g., estimate for global cognition [95% confidence interval] was -0.028 [-0.032 to -0.025]) and over the 2-year study (e.g., estimate for 2-year changes in ANU-ADRI and per-year changes in global cognition [95% confidence interval] was -0.068 [-0.026 to -0.108]). No significant beneficial intervention effect was reported for ANU-ADRI, and baseline ANU-ADRI did not significantly affect the response to the intervention on changes in cognition. CONCLUSIONS: The ANU-ADRI was effective for the risk prediction of cognitive decline. Risk scores may be crucial for the success of novel dementia prevention strategies, but their algorithm, the target population, and the intervention design should be carefully considered when choosing the appropriate tool for each context.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/prevention & control , Alzheimer Disease/epidemiology , Australia/epidemiology , Universities , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/etiology , Cognitive Dysfunction/prevention & control , Life Style , Cognition/physiology
18.
Lancet Healthy Longev ; 5(2): e120-e130, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38310892

ABSTRACT

BACKGROUND: It is unknown whether multidomain interventions, which might preserve late-life cognition, affect Alzheimer's disease pathology. Previous studies measured cerebrospinal fluid and imaging Alzheimer's disease biomarkers in small subsamples of multidomain trial participants. Newly developed assays enable the measurement of blood-based Alzheimer's disease biomarkers in larger samples. We aimed to assess whether plasma tau phosphorylated at threonine 181 (p-tau181) was able to detect or predict 3-year multidomain intervention effects. METHODS: This is a secondary analysis of the randomised, controlled, Multidomain Alzheimer Prevention Trial (MAPT) testing a 3-year multidomain intervention, omega-3 fatty acid supplementation, or both versus placebo, in individuals aged 70 years and older in 13 memory centres in France and Monaco. Plasma p-tau181 was measured in stored blood samples in a subsample of 527 participants on an intention-to-treat basis. Changes in cognitive score were calculated as a composite measure using the average of Z scores for the following tests: Mini Mental State Examination orientation items, Free and Cued Selective Reminding Test (sum of free and total recall scores), category fluency, and Digit Symbol Substitution Test. Intervention effects on 3-year change in p-tau181 concentration were estimated by use of a linear mixed model with centre-specific random intercepts. FINDINGS: Recruitment took place between May 30, 2008, and Feb 24, 2011. Median baseline plasma p-tau181 was 8·8 pg/mL (IQR 6·7-11·9) in the total sample, and significantly higher in older individuals, men, APOE ε4 carriers, and participants with renal dysfunction or a positive PET amyloid scan. During 3-year follow-up, individuals with raised baseline p-tau181 underwent greater cognitive decline (eg, mean difference in 3-year change on the composite cognitive score between control group participants with normal and abnormal baseline levels of p-tau was -0·34 [effect size -0·52; 95% CI -0·61 to 0·07] in the fully adjusted model using a 12·4 pg/mL cutoff for abnormal baseline p-tau181), but there were no intervention effects on change in p-tau181 either in this subgroup or the total population, and no effect on cognitive change in individuals with raised baseline p-tau181 (eg, in the fully adjusted model using the 12·4 pg/mL cutoff for p-tau181 abnormality, the mean difference [95% CI] in this subgroup in 3-year decline on the composite cognitive score between the control group and the multidomain + omega-3 group, the omega-3 group, and the multidomain intervention group, was, respectively: 0·13 [-0·21 to 0·47], 0·03 [-0·30 to 0·36], and 0·10 [-0·26 to 0·46]). Surprisingly, individuals with raised baseline p-tau181 showed a decrease in p-tau181 during follow-up (eg, unadjusted mean [95% CI] 3-year change was -3·01 pg/mL (-4·45 to -1·56) in control group subjects with abnormal baseline p-tau181 [using the 12·4 pg/mL abnormal p-tau cutoff]). INTERPRETATION: Our results support the utility of p-tau181 as a prognostic biomarker, but it did not predict or detect intervention effects in this study. Further investigation of its usefulness as a prevention trial outcome measure is required. FUNDING: Toulouse Gérontopôle, French Ministry of Health and Pierre Fabre Research Institute.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Aged , Aged, 80 and over , Humans , Male , Alzheimer Disease/diagnosis , Alzheimer Disease/prevention & control , Biomarkers , Cognition , Research Design , Female , Randomized Controlled Trials as Topic
19.
Medicine (Baltimore) ; 103(6): e37021, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38335403

ABSTRACT

We conducted a study to evaluate the impact of folic acid supplementation on the risk of Alzheimer disease (AD). A Mendelian randomization (MR) analysis model assessed the causal effects of folic acid supplementation on AD, utilizing data from recent genome-wide association studies. Effect estimates were scrutinized using various methods: inverse-variance weighted (IVW), simple mode, weighted mode, simple median, weighted median, penalized weighted median, and the MR-Egger method. The sensitivity analysis assessed heterogeneity and pleiotropy of individual single nucleotide polymorphisms (SNPs) using the IVW method with Cochran Q statistics and MR Egger intercept, respectively. Additionally, a leave-one-out sensitivity analysis determined potential SNP-driven associations. Both fixed-effect and random-effect IVW models in the MR analysis revealed a reduced risk of AD associated with folic acid supplementation (odds ratio, 0.930; 95% CI, 0.903-0.958, P < .001; odds ratio, 0.930; 95% CI, 0.910-0.950, P < .001) based on 7 SNPs as instrumental variables. The reverse MR analysis indicated no causal association between AD and folic acid supplementation. This study, utilizing genetic data, suggests that folic acid supplementation may potentially reduce the risk of AD and provides novel insights into its etiology and preventive measures.


Subject(s)
Alzheimer Disease , Folic Acid , Humans , Folic Acid/therapeutic use , Alzheimer Disease/epidemiology , Alzheimer Disease/genetics , Alzheimer Disease/prevention & control , Genome-Wide Association Study , Mendelian Randomization Analysis , Dietary Supplements
20.
Nature ; 627(8002): 149-156, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38418876

ABSTRACT

The glymphatic movement of fluid through the brain removes metabolic waste1-4. Noninvasive 40 Hz stimulation promotes 40 Hz neural activity in multiple brain regions and attenuates pathology in mouse models of Alzheimer's disease5-8. Here we show that multisensory gamma stimulation promotes the influx of cerebrospinal fluid and the efflux of interstitial fluid in the cortex of the 5XFAD mouse model of Alzheimer's disease. Influx of cerebrospinal fluid was associated with increased aquaporin-4 polarization along astrocytic endfeet and dilated meningeal lymphatic vessels. Inhibiting glymphatic clearance abolished the removal of amyloid by multisensory 40 Hz stimulation. Using chemogenetic manipulation and a genetically encoded sensor for neuropeptide signalling, we found that vasoactive intestinal peptide interneurons facilitate glymphatic clearance by regulating arterial pulsatility. Our findings establish novel mechanisms that recruit the glymphatic system to remove brain amyloid.


Subject(s)
Alzheimer Disease , Amyloid , Brain , Cerebrospinal Fluid , Extracellular Fluid , Gamma Rhythm , Glymphatic System , Animals , Mice , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/prevention & control , Amyloid/metabolism , Aquaporin 4/metabolism , Astrocytes/metabolism , Brain/cytology , Brain/metabolism , Brain/pathology , Cerebrospinal Fluid/metabolism , Disease Models, Animal , Extracellular Fluid/metabolism , Glymphatic System/physiology , Interneurons/metabolism , Vasoactive Intestinal Peptide/metabolism , Cerebral Cortex/cytology , Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Electric Stimulation
SELECTION OF CITATIONS
SEARCH DETAIL
...